Parts of a Frog's Muscular System

Frogs are one of Mother Nature's most amazing creations. Highly skilled and specialized hunters, frogs are able to jump long distances and capture prey from afar with their long tongues. Frogs have unique muscular and skeletal systems that allow them to thrive in their natural environment. Whether they're leaping, swimming or hopping, frogs move with grace and power thanks to their remarkable anatomy.

Involuntary Muscles

A frog's inner organs are controlled by involuntary or smooth muscles. Involuntary muscles work automatically and perform essential life functions, even while the frog is sleeping. Sympathetic and parasympathetic neurons in the brain send messages to and from these muscles. Involuntary muscles control the frog's digestive system, which includes the esophagus, stomach, small and large intestine, and rectum. They also pump the frog's heart. Frogs do not have a diaphragm for breathing because they absorb oxygen through their skin.

Voluntary Muscles

Frog's also have voluntary or striated muscles attached to their skeleton. They perform tasks such as jumping and swimming, and any other voluntary movements. Frogs have many of the same voluntary muscles as humans, like the deltoids and pectorals that control arm and chest movements. Frogs have a large shinbone, the tibiofibula, which allows them to jump long distances. Attached to this are the triceps femoris, sartorius, glacilis major, glacilis minor and semitendinousus. Frogs also have flexors and extenders near the joints that allow them to flex their wrists and ankles.

Skeleton

A frog's skeletal structure is similar to man's, though there are some key differences. The frog has nine vertebrae (man has 24), and this limits the frog's ability to bend its back. Frogs also do not have ribs. Adult frogs don't have tails, though in adolescence they are seen with tails as they are still developing out of the tadpole stage. Frogs only have one forearm bone called the radio-ulna, whereas man has two.

Jumping

Perhaps a frog's most remarkable skill is its ability to jump long distances quickly. During a jump, the hind legs provide most of the force. The semimembranosus muscle, which connects the pelvis with a point just below the knee, contracts and pulls the upper hind leg backward. This contraction generates enough power to propel the frog forward. When landing, the frog extends its forearm and the shoulder absorbs most of the impact.

Tongue

A frog's tongue is an amazing instrument used for capturing prey at a distance. It's about one-third the length of the frog and is attached to the front of the mouth rather than the back. When the frog catches its prey, the tongue becomes stiffer than normal. Suddenly, the tongue shoots out and captures the fly, retracts quickly into the mouth and tosses the food down the frog's throat.

References

• Anatomy of Amphibians
• Frog Functions
• Frog Facts - What's With That Tongue?